sysdeps/powerpc/bits/setjmp.h

   1 /* Copyright (C) 1997, 1998, 2000, 2003, 2004 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 /* Define the machine-dependent type `jmp_buf'.  PowerPC version.  */
  20 #ifndef _BITS_SETJMP_H
  21 #define _BITS_SETJMP_H  1
  22
  23 #if !defined _SETJMP_H && !defined _PTHREAD_H
  24 # error "Never include <bits/setjmp.h> directly; use <setjmp.h> instead."
  25 #endif
  26
  27 /* The previous bits/setjmp.h had __jmp_buf defined as a structure.
  28    We use an array of 'long int' instead, to make writing the
  29    assembler easier. Naturally, user code should not depend on
  30    either representation. */
  31
  32 #include <bits/wordsize.h>
  33
  34 #if defined __USE_MISC || defined _ASM
  35 # define JB_GPR1   0  /* Also known as the stack pointer */
  36 # define JB_GPR2   1
  37 # define JB_LR     2  /* The address we will return to */
  38 # if __WORDSIZE == 64
  39 #  define JB_GPRS   3  /* GPRs 14 through 31 are saved, 18*2 words total.  */
  40 #  define JB_CR     21 /* Condition code registers with the VRSAVE at */
  41                        /* offset 172 (low half of the double word.  */
  42 #  define JB_FPRS   22 /* FPRs 14 through 31 are saved, 18*2 words total.  */
  43 #  define JB_SIZE   (64 * 8) /* As per PPC64-VMX ABI.  */
  44 #  define JB_VRSAVE 21 /* VRSAVE shares a double word with the CR at offset */
  45                        /* 168 (high half of the double word).  */
  46 #  define JB_VRS    40 /* VRs 20 through 31 are saved, 12*4 words total.  */
  47 # else
  48 #  define JB_GPRS   3  /* GPRs 14 through 31 are saved, 18 in total.  */
  49 #  define JB_CR     21 /* Condition code registers.  */
  50 #  define JB_FPRS   22 /* FPRs 14 through 31 are saved, 18*2 words total.  */
  51 #  define JB_SIZE   ((64 + (12 * 4)) * 4)
  52 #  define JB_VRSAVE 62
  53 #  define JB_VRS    64
  54 # endif
  55 #endif
  56
  57
  58 /* The current powerpc 32-bit Altivec ABI specifies for SVR4 ABI and EABI
  59    the vrsave must be at byte 248 & v20 at byte 256.  So we must pad this
  60    correctly on 32 bit.  It also insists that vecregs are only gauranteed
  61    4 byte alignment so we need to use vperm in the setjmp/longjmp routines.
  62    We have to version the code because members like  int __mask_was_saved
  63    in the jmp_buf will move as jmp_buf is now larger than 248 bytes.  We
  64    cannot keep the altivec jmp_buf backward compatible with the jmp_buf.  */
  65 #ifndef _ASM
  66 # if __WORDSIZE == 64
  67 typedef long int __jmp_buf[64] __attribute__ ((__aligned__ (16)));
  68 # else
  69 /* The alignment is not essential, i.e.the buffer can be copied to a 4 byte
  70    aligned buffer as per the ABI it is just added for performance reasons.  */
  71 typedef long int __jmp_buf[64 + (12 * 4)] __attribute__ ((__aligned__ (16)));
  72 # endif
  73 #endif
  74
  75 /* Test if longjmp to JMPBUF would unwind the frame
  76    containing a local variable at ADDRESS.  */
  77 #define _JMPBUF_UNWINDS(jmpbuf, address) \
  78   ((void *) (address) < (void *) (jmpbuf)[JB_GPR1])
  79
  80 #endif  /* bits/setjmp.h */